Two masses 1.2kg and 1.8kg are connected to the ends of a rod of length 2m. Find the moment of inertia about the axes, 1)going through the mid point of the rod. 2)going through the centre of mass of two masses.​

Answer:

the amplitude of the sequence oscillation=

ASO = length × velocity

= 9.8 × 0.2 = 19.6

ASO = 19.6

If the box is moving at constant velocity, net force must be zero, so:

F + fr = 0

fr = -F

fr = -40 N

Complete Question

1 a A little girl pushes a 5.0 kg toy baby stroller at constant speed 7.0 m across the floor. She pushes on the handle with a force of 40 N at an angle of 30o with the horizontal.  How much work is done by the girl on the wagon?

1b  A farmhand pushes 20 ㎏ bale of hay 4m across the floor of the barn if she exerts a horizontal force of 60 N on the hay, how much work is done? (5 pts)

All parts are 4 points each

Answer:

1a

  [tex]W = 242.5 \ J[/tex]

1b

    [tex]W = 240 \ J[/tex]

Explanation:

Considering question a

From the question we are told that

       The mass of the toy baby stroller is  [tex]m = 5.0 \ kg[/tex]

        The distance covered is    [tex]d = 7.0\ m[/tex]

          The force the girl applies on the handle  is  [tex]F = 40 \ N[/tex]

          The angle at which this force is applied is  [tex]\theta = 30^o[/tex]

Generally the workdone is mathematically represented as

          [tex]W = F_x * d[/tex]

Here  [tex]F_x[/tex] is the force along the horizontal axis , this is mathematically represented as

           [tex]F_x = F cos (\theta )[/tex]

=>         [tex]F_x = 40 * cos(30 )[/tex]

=>         [tex]F_x = 34.64 \ N[/tex]

So

              [tex]W = 34.64 * 7[/tex]

=>           [tex]W = 242.5 \ J[/tex]

Considering question b

From the question we are told that

       The mass of the toy baby stroller is  [tex]m = 20 \ kg[/tex]

        The distance covered is    [tex]d = 4 \ m[/tex]

          The force the girl applies on the handle  is  [tex]F = 60 \ N[/tex]      

Generally the workdone is mathematically represented as

          [tex]W = F * d[/tex]

=>     [tex]W = 60 * 4[/tex]

=>     [tex]W = 240 \ J[/tex]

Answer:

the nucleus is the size of an apple, approximately 5 cm of radius e, the atom has a radius of R = 5 cm 104 = 50000 cm = 50 km

Explanation:

In the Rutherford experiments it was proved that the atomic nucleus has the volume 10-4 the volume of the atom.

If we make a scale design in which the nucleus is the size of an apple, approximately 5 cm of radius e, the atom has a radius of R = 5 cm 104 = 50000 cm = 50 km

This shows that almost the entire volume of the atom is empty.

Answer:

A. The sum of all the forces acting on an object.

Answer:

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 3.8 × 2.5

We have the final answer as

Hope this helps you

Answer:

1.62 m/s

Explanation:

Wavelength of the water wave= 54 m

The frequency is 0.03 Hz

Therefore the velocity can be calculated as follows

Velocity= frequency × wavelength

= 0.03 × 54

= 1.62 m/s

Answer:

velocity = 16.05 m/s

Explanation:

inelastic collision formula:

m1u1 + m2u2 = (m1 + m2)v

m1 = 4kg

u1 = 20m/s

m2 = 15kg

u2 = 15m/s

find v ?

m1u1 + m2u2 = (m1 + m2)v

(4×20) + (15×15) = (4+15)v

80 + 225 = 19v

305 = 19v

19v = 305

v = 305/19

v = 16.05 m/s

Answer:

you can show them a vid

Explanation:

Answer:

can you include a picture

Decompose the forces acting on the rocket in horizontal and vertical components.

• net horizontal force:

∑ F = (12.3 N) cos(65°) - 2.5 N ≈ 2.7 N

(notice we're taking "to the right" to be the positive direction)

• net vertical force:

∑ F = (12.3 N) sin(65°) - 1.2 N ≈ 9.9 N

The resultant force then has magnitude

√((2.7 N)² + (9.9 N)²) ≈ 10.3 N

Since the horizontal and vertical components of the resultant are both positive, it points at an angle between 0° and 90° from the positive horizontal, so that

tan(θ) ≈ (9.9 N) / (2.7 N) ≈ 3.69

===>   θ ≈ arctan(3.69) ≈ 75°

Answer:

Speed. I am speed.

Explanation:

The FitnessGram Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. A single lap should be completed each time you hear this sound. Remember to run in a straight line, and run as long as possible.

Answer: It’s fastest in gases. Letter C !

Explanation:

Answer:

its c

Explanation:

Answer:

β = 114 db

Explanation:

The intensity of sound in decibles is

          β = 10 log [tex]\frac{I}{I_{o}}[/tex]

in most cases Io is the hearing threshold 1 10-12 W / cm²

let's calculate the intensity of each instrument

            I / I₀ = 10 (β / 10)

            I = I₀ 10 (β / 10)

trumpet

            I1 = 1 10⁻¹² 10 (94/10)

            I1 = 2.51 10⁻³ / cm²

Thrombus

           I2 = 1 10⁻¹² 10 (107/10)

           I2 = 5.01 10-2 W / cm²

low

           I3 =1 1-12    (113/10) W/cm²

            I3 = 1,995 10-1 W / cm²

when we place the three instruments together their sounds reinforce

           I_total = I₁ + I₂ + I₃

           I_ttoal = 2.51 10-3 + 5.01 10-2 + ​​1.995 10-1

           I_total = 0.00251 + 0.0501 + 0.1995

           I_total = 0.25211 W / cm²

let's bring this amount to the SI system

         β = 10 log (0.25211 / 1 10⁻¹²)

           β = 114 db

Answer:

B. 85.4 N

Explanation:

The tension in the rope at the lowest point of the motion of the ball is antiparallel to the weight of the ball. By Newton's laws we construct the following equation of equilibrium:

[tex]\Sigma F = T - W = \left(\frac{W}{g} \right)\cdot \frac{v^{2}}{L}[/tex] (1)

Where:

[tex]T[/tex] - Tension in the rope, measured in newtons.

[tex]W[/tex] - Weight, measured in newtons.

[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.

[tex]v[/tex] - Speed of the ball, measured in meters per second.

[tex]L[/tex] - Length of the rope, measured in meters.

If we know that [tex]W = 60\,N[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]v = 5\,\frac{m}{s}[/tex] and [tex]L = 6\,m[/tex], then the tension in the rope at this point is:

[tex]T = W+\frac{W\cdot v^{2}}{g\cdot L}[/tex]

[tex]T = W\cdot \left(1+\frac{v^{2}}{g\cdot L} \right)[/tex]

[tex]T = (60\,N)\cdot \left[1+\frac{\left(5\,\frac{m}{s} \right)^{2}}{\left(9.807\,\frac{m}{s^{2}} \right)\cdot (6\,m)} \right][/tex]

[tex]T = 85.492\,N[/tex]

Hence, the correct answer is B.

Answer:

A) 5 m/s/s

Explanation:

Given the following data;

Initial velocity = 10m/s²

Final velocity = 20m/s²

Time, t = 2 seconds.

In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.

This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.

Hence, if we subtract the initial velocity from the final velocity and divide that by the time, we can calculate an object’s acceleration.

Mathematically, acceleration is given by the equation;

[tex]Acceleration, a = \frac{final \; velocity - initial \; velocity}{time}[/tex]

Substituting into the equation, we have;

[tex]Acceleration, a = \frac{20 - 10}{2}[/tex]

[tex]Acceleration, a = \frac{10}{2}[/tex]

Acceleration, a = 5m/s²

Answer:

D

Explanation:

because the whole town needs to be powered through some sort of energy and kinetic energy means the movement of something

The technology in the picture represents the conversion of kinetic energy to electrical energy. So, the correct option is D.

Kinetic energy of a body is defined as the energy acquired by the body due to the virtue of its motion.

Here,

The given picture represents the dam system at a town.

We know, according to conservation of energy, energy can neither be created nor be destroyed, but can be transferred from one form to another.

In the dam system, the application of conservation of energy is implemented.

Dam consists of a water stream and turbines. The water stream is arranged in such a way that, when the water is running from a height, the water acquires an energy in the form of kinetic energy.

This kinetic energy of the water is converted to electrical energy with the help of the turbines, which are rotating continuously and thus electricity is produced.

Hence,

The technology in the picture represents the conversion of kinetic energy to electrical energy.

To learn more about kinetic energy, click:

https://brainly.com/question/999862

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Answer:

A stunt person jumps from the roof of a tall building, but no injury occurs because the person lands on a large, air-filled bag. Which one of the following best describes why no injury occurs?

The bag increases the amount of time during which the momentum is changing and reduces the average force on the person.

ANSWER: A

Answer:

A. The bag increases the amount of time during which the momentum is changing and reduces the average force on the person.

During stunts, people usually put an-air filled bag on the ground for safe landing and to prevent injuries.

Momentum is calculated by m* v where m is for mass and v is for velocity.

Force is directly proportional to momentum

F∝M

The bag in this scenario helps to increases the amount of time the force acts on the person. This implication means that there is a reduction in the change of momentum. Since Force and momentum have a directly proportional relationship then the Force taken to hit the floor is greatly reduced.

Read more on https://brainly.com/question/20362316

Answer:Rolling friction is friction that acts on objects when they are rolling over a surface. Rolling friction is much weaker than sliding friction or static friction. This explains why most forms of ground transportation use wheels, including bicycles, cars, 4-wheelers, roller skates, scooters, and skateboards.

Explanation:

Answer:

P = 3.3075 x 10⁶ N/m² = 479.71 lb/in²

Explanation:

In order to find the pressure , we first need to find the force exerted by the lady. The force must be equal to the weight of the lady:

Force = F = Weight = mg

F = mg = (54 kg)(9.8 m/s²)

F = 529.2 N

Now, we convert area to S.I unit:

Area = A = (1.6 cm²)(1 m/100 cm)²

A = 1.6 x 10⁻⁴ m²

Now, the pressure can be calculated as:

Pressure = P = F/A

P = 529.2 N/1.6 x 10⁻⁴ m²

P = 3.3075 x 10⁶ N/m²

Now, we convert this into lb/in²:

P = (3.3075 x 10⁶ N/m²)[(0.000145038 lb/in²)/(1 N/m²)

P = 479.71 lb/in²

Answer:

i think the red runner travels greater distance ie.40 m

Explanation:

although ,the blue one travels 21 m but in the backward direction .so the correct ans is "the red runner travels 40 m"

Answer:

Explanation:

The the horizontal and vertical component be expressed as;

Fx = Fxos theta (horizontal compt)

Given Fx = 20N

theta = 30°

Get F:

20 = Fcos30

20 = 0.8660F

F = 20/0.8660

F = 23.09N

Get the magnitude of the other components. (vertical compt)

Fy = Fsin theta

Fy = 23.09sin30

Fy = 23.09(0.5)

Fy = 11.545N

Hence the magnitude of the other component is 11.545N

Answer:

Impulse = 0.1 Kgm/s

Explanation:

Given the following data;

Force, F = 10N

Time, t = 0.01 seconds

To find impulse

An impulse can be defined as the net force acting an object for a very short period of time.

Mathematically, impulse is given by the formula;

Impulse = force * time

Substituting into the equation, we have;

Impulse = 10 * 0.01

Impulse = 0.1 kgm/s

Therefore, the impulse of the hammer is 0.1 kilogram meter per seconds.

The impulse of the hammer is 0.1 Ns.

To solve the given problem we need to use the formula for calculating impulse.

Impulse: This can be defined as the product of force and time on a body.

The formula of impulse is given below.

I = Ft....................... Equation 1

Where :

From the question,

Given:

Substitute these values into equation 1

Hence, The impulse of the hammer is 0.1 Ns.

Learn more about force here: https://brainly.com/question/13370981

A ripcord system pulls a closing pin, which releases a spring-loaded pilot chute, and opens the container; from which the parachute comes out.

If a skydiver is unable to open her/his parachute, an automatic activation device will automatically open the parachute.

A parachute works by forcing air into the front of it and creating a structured 'wing' under which the canopy pilot can fly. Parachutes are controlled by pulling down on steering lines which change the shape of the wing, cause it to turn, or to increase or decrease its rate of descent.

Answer:

Power_input = 85.71 [W]

Explanation:

To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.

[tex]W = F*d[/tex]

where:

W = work [J] (units of Joules)

F = force [N] (units of Newton)

d = distance [m]

We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.

Now replacing:

[tex]W = (80*10)*3\\W = 2400 [J][/tex]

Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.

[tex]P=\frac{W}{t}[/tex]

where:

P = power [W] (units of watts)

W = work [J]

t = time = 40 [s]

[tex]P = 2400/40\\P = 60 [W][/tex]

The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.

[tex]Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}=60/0.7\\P_{introduced}=85.71[W][/tex]

Answer:

182.28 W

Explanation:

Here ,

m = 7.30 Kg

distance , d= 28.0 m

time , t = 11.0 s

average power supplied = change in potential energy/time

average power supplied = m×g×d/time

average power supplied = 7.30×9.81×28/11

average power supplied = 182.28 W

the average power supplied is  182.28 W

Answer:

a) Weight of Roommate = 481.4 N

b) μk = 0.34

Explanation:

a)

The force required to move the couch must be equal to the force of friction:

F = frictional force

F = μW

W = F/μ

where,

W = Total Weight of Couch and Roommate

F = Force Required start to move couch = 250 N

μ = coefficient of static friction between couch and floor = 0.43

Therefore,

[tex]W = \frac{250 N}{0.43}\\\\W = 581.4 N[/tex]

So, the total weight is given as:

W = Weight of Couch + Weight of Roommate

Weight of Roommate = W - Weight of Couch

Weight of Roommate = 581.4 N - 100 N

Weight of Roommate = 481.4 N

b)

Now, the force required to keep the couch moving can be given as equal to the kinetic friction force:

F = kinetic friction

F = μk*W

μk = F/W

where,

μk = coefficient of kinetic friction = ?

F = Force required to keep the couch moving = 200 N

Therefore,

μk = 200 N/581.4 N

μk = 0.34